Antimicrobial Activity of Lactobacillus acidophilus Isolated from Breast Milk In Vitro

Abstract

Probiotics are used as a method to prevent many disorders and treat diseases. Lactobacillus acidophilus was isolated from breast milk with the intention of studying their properties as probiotics in view of their importance isolates to simulate gastric juice antibacterial activity of bacteria isolates against enteric pathogenic bacteria. Evaluation of five positive samples out of 102 have been isolated and identified, by using selective media (MRS-VA), biochemical tests and molecular diagnosis using the 16S rRNA gene. The probiotic potential was assessed by determining antibiotic susceptibility through the disc diffusion method. Among five isolates, lactobacillus acidophilus was also highly resistant to simulated gastric environment, though there was a decreasing by 0.287 after incubation for three hours at 37 ºC in the simulated gastric juice with pH 2.5. Lactobacillus acidophilus exhibited a strong antimicrobial effect against the selected gram-negative salmonella typhimurium, and E. coli. Also, gram-positive staphylococcus aureus pathogens. The very small p-values (p = 0.001**). Based on findings, isolated lactobacillus acidophilus displayed promising probiotic characteristics, highlighting human milk as a potential source of these beneficial bacteria.